Directions

In a large pot, bring 6 cups of lightly salted water to a boil. Add the uncooked macaroni and cook for about 8-10 minutes, until tender. Rinse under cold water and drain.
In a large bowl, mix together the mayonnaise, vinegar, sugar, mustard, salt and pepper. Stir in the onion, carrots, green pepper, and macaroni. Refrigerate for at least 4 hours before serving, but preferably overnight.